To provide a magnetizing method for forming a plurality of magnetic poles spaced at intervals of a very small distance in a member to be magnetized, having a magnetic layer formed on an endless peripheral surface or in the vicinity thereof, in which the magnetized magnetic poles have high magnetic flux density and uniform intensity.

A magnetizing head 3 is positioned as making contact with or close to a peripheral surface of a member to be magnetized 2 a D.C. magnetizing current is passed through an excitation coil 18 of the head to form magnetic flux passing through a magnetic layer nearly perpendicular to the peripheral surface of the member. Then the head is moved in an axial direction of the member, i.e., in a width direction of the endless peripheral surface to magnetize the magnetic layer. When the head reaches the end of a zone where one magnetic pole is to be provided, the peripheral surface of the member is moved by only a predetermined amount in the peripheral direction to move the head in the opposite direction, and at the same time, a D.C. current in a direction opposite to the above magnetizing current is applied to the excitation coil. Such as operation is repeated to magnetize the member along the full periphery of the member.